In Vitro Contraction of Isolated Cauda Epididymal Duct Smooth Muscle as a Complimentary Approach to Physiological, Pathological, Toxicological, and Pharmacological Studies on Epididymal Function.

Contraction of cauda epididymal duct (CE) smooth muscle is one of the very first events of the seminal emission phase of ejaculation. The contraction of CE smooth muscle is governed by a complex interaction of hormones, autacoids, and by the neurotransmitters released from the epididymal intramural nerve endings, and any impairment in the CE smooth muscle contraction has the potential to impair male fertility. Apart the obvious pathophysiological and toxicological importance of CE smooth muscle contraction, modulation of CE contraction has pharmaceutical interest offering a druggable target to development of drugs to improve/impair male fertility.

Contractile Effects of Serotonin (5-HT) in the Rat Cauda Epididymis: Expression and Functional Characterization of 5-HT Receptors.

Serotonin [5-hydroxytryptamine (5-HT)] exerts multiple central and peripheral functions. High concentrations of 5-HT have been found in the epididymis, a ductal organ that plays pivotal roles in sperm transport and maturation. The contraction of the epididymal smooth muscle is essential for sperm transport and emission during ejaculation.

Contraction of Rat Cauda Epididymis Smooth Muscle to -Adrenoceptor Activation Is Mediated by -Adrenoceptors.

The cauda epididymis (CE), the site of sperm storage until the ejaculation, is densely innervated by the sympathetic nervous system. Contraction of CE smooth muscle via -adrenoceptors (-ARs) plays a key role during the seminal emission phase of ejaculation and -AR antagonism has been suggested as a nonhormonal and reversible male contraceptive target. Since the -AR subtype mediating contraction of rat CE is not known, this study investigates the expression and role of -AR subtypes on the proximal and distal rat CE duct contraction to norepinephrine in vitro.

Cardiac hyporesponsiveness in severe sepsis is associated with nitric oxide-dependent activation of G protein receptor kinase.

G protein-coupled receptor kinase isoform 2 (GRK2) has a critical role in physiological and pharmacological responses to endogenous and exogenous substances. Sepsis causes an important cardiovascular dysfunction in which nitric oxide (NO) has a relevant role. The present study aimed to assess the putative effect of inducible NO synthase (NOS2)-derived NO on the activity of GRK2 in the context of septic cardiac dysfunction.

Long-term adverse effects on reproductive function in male rats exposed prenatally to the glucocorticoid betamethasone.

Betamethasone is the drug of choice for antenatal treatment, promoting fetal lung maturation, decreasing the incidence of respiratory distress syndrome and neonatal mortality. Previous studies reported that prenatal treatment with this drug reduced testosterone levels, sperm quality and fertility in adult rats. We aimed to further evaluate the reproductive consequences of prenatal betamethasone exposure in male rats.

The Coadministration of N-Acetylcysteine Ameliorates the Effects of Arsenic Trioxide on the Male Mouse Genital System.

Arsenic trioxide (As2O3) has shown effectiveness in treatment of leukemia but is also associated with reproductive toxicity. Since remediation with N-acetylcysteine (NAC) may mitigate the adverse effects caused by exposure, we assessed the effects of As2O3 and its potential reversibility after exposure cessation or coadministration of NAC. Animals received 0.

Slimmer or fertile? Pharmacological mechanisms involved in reduced sperm quality and fertility in rats exposed to the anorexigen sibutramine.

Sperm acquire motility and fertility capacity during epididymal transit, under the control of androgens and sympathetic innervations. It is already known that the acceleration of epididymal sperm transit time can lead to lower sperm quality. In a previous work we showed that rats exposed to the anorexigen sibutramine, a non-selective serotonin-norepinephrine reuptake inhibitor, presented faster sperm transit time, lower epididymal sperm reserves and potentiation of the tension of epididymal duct to norepinephrine exposed acutely in vitro to sibutramine.

Acceleration of sperm transit time and reduction of sperm reserves in the epididymis of rats exposed to sibutramine.

Sibutramine is a drug globally used for the treatment of obesity. The aim of this study was to investigate male reproductive disorders caused by sibutramine in adult rats. Wistar rats were treated for 28 consecutive days (gavage) with 10 mg/kg of sibutramine.